Screening of 20 Commonly Used Iranian Traditional Medicinal Plants Against Urease

Infection with Helicobacter pyloriis the most common cause of stomach and duodenal ulcers. About more than 80 % of people are infected with H. pylori in developing countries. H. pyloriuses urease enzyme product “ammonia” in order to neutralize and protect itself from the stomach acidic condition and urease enzyme activity has been shown to be essential to the colonization of H. pylori. Inhibitory activity of 20 traditional medicinal plants were examined and evaluated against Jack bean urease activity by Berthelot reactionto obtain natural sources of urease inhibitors. Each herb was extracted using 80% aqueous methanol, then tested its IC50 value was determined. Eight of the whole 20 studied plants crude extracts were found the most effective with IC50 values of less than 100µg/ml including Laurus nobilis, Zingiber officinale, Nigella sativa, Angelica archangelica, Acorus calamus, Allium sativum,Curcuma longa, andCitrus aurantiumextracts,from which most potent urease inhibitory was observed for Zingiber officinale, Laurus nobilis, and Nigella sativa with IC50values of 48.54, 48.69 and 59.10µg/ml, respectively.